Apparatus and Method for Reducing Color Error in Display Having Sub-Pixel Structure

1. A method of displaying image data comprising a plurality of pixels each comprising at least two sub-pixels, the method comprising: setting at least two directions relative to a target sub-pixel to be displayed; calculating, for each of the set directions, differences of brightness values of at least two pixels or sub-pixels positioned in the each of the set directions in current input image data, one of the at least two pixels or sub-pixels positioned on one side of the target sub-pixel and another of the at least two pixels or sub-pixels positioned on the other side of the target sub-pixel; selecting one of the differences and determining a reference direction indicated by the selected difference; selecting in the reference direction at least one sub-pixel or pixel neighboring the target sub-pixel to be displayed; and filtering a brightness value of the target sub-pixel to be displayed and a brightness value of the at least one sub-pixel or pixel which is selected and re-assigning the filtered brightness value to the sub-pixel to be displayed.

2. The method of claim 1 , wherein the sub-pixels constitute the plurality of pixels sequentially on a space that is a stripe structure.

3. The method of claim 1 , wherein the calculating the differences of brightness values comprises differences between brightness values of pixels or sub-pixels positioned in an opposite direction to the reference direction.

4. The method of claim 3 , wherein a number of the set directions is 10.

5. The method of claim 1 , wherein the at least one sub-pixel is selected from sub-pixels positioned in the reference direction and sub-pixels neighboring the reference direction.

6. The method of claim 5 , wherein if the sub-pixels form a stripe structure in an order of R, G, and B, a sub-pixel determined with respect to a sub-pixel “R” is positioned on a left side compared to a sub-pixel determined with respect to a sub-pixel “B.”

7. The method of claim 1 , wherein the reference direction is selected according to one of the largest and smallest differences of the differences between the at least two brightness values.

8. A display for displaying image data comprising a plurality of pixels each comprising at least two sub-pixels, the display comprising: a measurer which measures, for each of a plurality of directions, differences of brightness values of at least two pixels or sub-pixels positioned in the each of the directions in current input image data, one of the at least two pixels or sub-pixels positioned on one side of a target sub-pixel and another of the at least two pixels or sub-pixels positioned on the other side of the target sub-pixel in the direction according to a control command; a selector which compares the differences of the brightness values from the measurer and selects one of the differences as a reference direction; a controller which selects a sub-pixel to be displayed and at least one pixel or sub-pixel neighboring the sub-pixel to be displayed in the reference direction; and a filter filtering which filters a brightness value of the sub-pixel to be displayed and brightness values of the selected at least one pixel or sub-pixel according to the control command output from the controller.

9. The display of claim 8 , wherein the controller re-assigns the filtered brightness value to the sub-pixel to be displayed and instructs a display unit to display the sub-pixel having the re-assigned brightness value.

10. The display of claim 8 , wherein the sub-pixels constitute the plurality of pixels sequentially on a space such as a stripe structure.

11. The display of claim 8 , wherein the at least one sub-pixel is selected from sub-pixels positioned in the reference direction and sub-pixels neighboring the reference direction.

12. The display of claim 8 , wherein the reference direction is selected according to one of the largest and smallest differences of the differences between the at least two brightness values.

13. A method of display image data comprising a plurality of pixels each comprising at least two sub-pixels, the method comprising: setting at least two directions relative to a target sub-pixel to be displayed; calculating differences of brightness values of at least two pixels or sub-pixels positioned in the each of the set direction in current input image data, one of the at least two pixels or sub-pixels positioned on one side of the target sub-pixel and another of the at least two pixels or sub-pixels positioned on the other side of the target sub-pixel in each of the set directions; selecting one of the differences and determining a reference direction indicated by the selected difference; determining a filter for filtering at least one sub-pixel or pixel neighboring the target sub-pixel to be displayed in the reference direction; and filtering a brightness value of the target sub-pixel to be displayed and a brightness value of the at least one sub-pixel or pixel which is selected and re-assigning the filtered brightness value to the target sub-pixel to be displayed.

14. The method of claim 1 , wherein: calculating differences of the brightness values comprises calculating, for each of the set directions, the difference of brightness values between a first pixel or sub-pixel on the one side of the target sub-pixel and a second pixel or sub-pixel on the another side of the target sub-pixel, and between a third pixel or sub-pixel on the one side of the target sub-pixel and a fourth pixel or sub-pixel on the another side of the target sub-pixel; and the method further comprises: calculating, for each of the set directions, a gradient of the set direction comprising an average of the difference between the first pixel or sub-pixel and the second pixel or sub-pixel, and the difference between the third pixel or sub-pixel and the fourth pixel or sub-pixel; and wherein determining the reference direction comprises comparing the gradients of the set directions and determining a largest or smallest gradient as the reference direction.

15. The method of claim 1 , wherein the at least two pixels or sub-pixels are of a same color as the target sub-pixel.